Importance of the ECG in Athletes

Electrocardiographic (ECG) interpretation in athletes continues to evolve as clinicians attempt to balance two competing priorities: 1) identifying occult cardiovascular disease; and 2) minimizing false-positive screening results that cause unnecessary downstream testing and sport restriction. The goals of updating the criteria include reducing false-positive and false-negative results, minimizing interobserver variability and experience. Earlier criteria dramatically reduced false-positive rates from approximately 17% to close to 3-4%.¹

Updated International Criteria

The 2025 International Summit on ECG Interpretation in Athletes (IC25) convened on Sept. 25-26, 2025 for a highly anticipated update to the 2017 international criteria. The European Association of Preventive Cardiology (EAPC) published a consensus statement on remarkable ECG findings in athletes the same weekend, reinforcing several themes discussed throughout the meeting and further supporting the evolving direction of athlete ECG interpretation.¹

The updated international criteria focus on the previously defined borderline category. In anticipation of the forthcoming update, this expert analysis highlights three topics from IC25: 1) T-wave inversions (TWIs); 2) athlete anterior early repolarization pattern (AERP); and 3) premature ventricular contractions (PVCs).

T-Wave Inversions

TWIs are defined by negative T waves ≥1 mm or 0.1 mV in at least two contiguous leads, excluding leads aVR, III, and V₁. The distribution is classified as anterior (leads V₂ through V₄), inferior (leads II or aVF), or lateral (leads V₅ and/or V₆, I, and aVL).

TWIs are considered a normal variant if they:

• Are confined to leads V₁ or V₂; or
• Are present in leads V₁ through V₃ in individuals <16 years of age (juvenile T-wave pattern); or
• Extend to leads V₁ through V₄ when preceded by J-point elevation/ST-segment elevation (i.e., AERP).

Anticipated changes include:

• New to the yellow box/may require evaluation category will be TWI in leads V₁ through V₃ in females ≥16 years of age; and
• Any TWI in the lateral leads (defined as any TWI in the lateral leads; TWI in leads I and aVL and either lead V₅ or V₆, or both is considered the red box/further evaluation category).

Athlete Anterior Early Repolarization Pattern

The 2017 international criteria defined the Black athlete early repolarization pattern or Black athlete ECG as anterior TWIs confined to leads V₁ through V₄ associated with convex ST-segment elevation.¹ This ECG pattern is not exclusively found in athletes who self-identify as Black. Recent data from 6,177 competitive athletes 15-25 years of age revealed 47 athletes with different self-identified races with this ECG pattern, also called the athlete anterior early repolarization pattern (overall prevalence 0.76%).² Ten-year follow-up showed no association of sudden death.² AERP was observed across multiple racial and ethnic groups, supporting a transition away from race-based definitions. Hsieh et al. later reported their single-center study on 670 professional athletes over 22 years.³ None of the 19 athletes in this study meeting AERP criteria had any identifiable adverse events over a mean follow-up of 10 years.³ Together, findings from Rim et al. and Hsieh et al. suggest that AERP may represent a benign manifestation of physiologic adaptation in competitive athletes rather than a marker of increased arrhythmic or sudden death risk in athletes who are otherwise free of symptoms.^2,3 During IC25, much discussion centered on keeping this ECG pattern in the green box/no further evaluation category and referring to it as the anterior early repolarization pattern in an effort to move away from race-based screening.

Premature Ventricular Contractions

A finding on a 12-lead ECG of at least two PVCs of any morphology, or one PVC with noninferior axis or short-coupling interval, is considered remarkable. Similar to other athlete ECG findings, the interpretation of these ECG findings should be guided by both ECG characteristics and overall clinical context. However, the discussion on PVCs emphasized the need to consider both the morphology and quantity of PVCs. Specifically, PVCs that originate from the right or left ventricular free walls are more frequently associated with underlying pathology. As such, a PVC from a structurally normal heart that is positive in leads II, III, and aVF reflects an inferior axis, likely outflow tract origin, and will be noted in the yellow box/may require evaluation category. However, a PVC that is negative in II, III, and aVF reflects a superior axis/noninferior axis and is unlikely to be from the outflow tracts or fascicles. This finding should raise concern for a pathologic mechanism until proven otherwise. In addition, a short-coupling interval defined as ≤350 msec from the start of the previous QRS to the start of the PVC was discussed as being higher risk for inducing ventricular fibrillation. Noninferior-axis PVCs and short-coupled PVCs will be highlighted in the red box/further evaluation category.

A Practical Framework for Clinicians

When reviewing an athlete's ECG, clinicians should broadly ask three questions:

• Is this finding expected for exercise-induced cardiac remodeling?
• Is this finding isolated or accompanied by other remarkable findings on the ECG?
• Does the patient's clinical context raise concern?

Findings that are isolated, physiologically expected, and present in an asymptomatic athlete without a concerning history are often low risk. In contrast, remarkable ECG patterns, symptoms, or a family history of cardiomyopathy or sudden cardiac death should lower the threshold for further testing.

Although TWI, AERP, and PVCs were three of the most discussed ECG findings in athletes, IC25 will have several modifications forthcoming. In addition, two systematic reviews and a modified Delphi study will be published concurrently to present data that will inform the discussions and final recommendations. IC25 promises to be the most rigorous criteria for athlete ECG interpretation to date.

References

1. Finocchiaro G, Zorzi A, Abela M, et al. Abnormal electrocardiogram findings in athletes. Eur Heart J. 2026;47(2):152-169. doi:10.1093/eurheartj/ehaf646
2. Rim AJ, Hsieh PN, Patel P, et al. Prevalence and outcomes of competitive athletes from the United States with electrocardiographic athletic anterior early repolarization. JACC Adv. 2025;4(9):102102. doi:10.1016/j.jacadv.2025.102102
3. Hsieh PN, Churchill TW, Petek BJ, et al. Prevalence and event-free follow-up of the athlete early repolarization pattern in professional athletes. JACC Clin Electrophysiol. 2026;12(7):1735-1737. doi:10.1016/j.jacep.2026.03.018